I have a solid MBP 2008 Unibody running on 10.6.7. With a fresh install, I have used about 988 MB of RAM from iStatMenu, right after boot-up. If I moved the exact same HDD to MBP 2011 i7, upon boot-up it will use 1.35GB RAM. The only difference I can see is that the MBP 2008 has 256 MB shared video memory and MBP 2011 has 384 MB. The only difference is about 128 MB, however, the net difference of RAM used after boot-up from the same HDD, it about 400 MB. Any idea where does the difference go? I mean afterall, it is the same OS and same drive with same apps loaded at boot time. 400 MB is quite a premium even if I have 8GB of RAM.